Wilfred eames



N0. 6l3,I27. Patented 001:. 25; I898.

-W. EAMES. TWIST DRILL GRINDER.

(Application filed Dec. 13, 1897.) (No Model.)

I I I I I IIIIIIIIIIIIIIIIIIIIIIIIIIIIH g flwllllllllllllllllflm a I F a? IIIIIIIIIIIIIIIIIIIIII UNITED, STATES FFICEQ PATENT VVILFRED EAMES, OF CLEVELAND, OHIO, ASSIGNOR TO \VILFRED EAMES 00., OF SAME PLACE.

TWIST-DRILL GRIN DER.

SJ? 1?.GI15I(1. YIION forming part of Letters Patent No. 613,127, dated October 25, 1898.

Application filed December 13, 1897. Serial No. 661,670. (No model.)

To all whom; it may concern.-

Be it known that I, WILFRED EAMES, of Cleveland, in the county of Ouyahoga and State of Ohio, have invented certain new and usefullmprovementsin Twist-Drill Grinders, of which the following is a full, clear, and exact description, reference being had to the accompan yin g drawings and to the numerals of reference marked thereon.

My invention relates to edge-tool-grinding machines,and particularly to that class known as twistdrill grinders, in the use of which a drill suitably supported is presented at an angle to the face of a grinding-wheel and While being ground is turned on an inclined pivot for the purpose of removing the stock back of the cutting edge or lip to produce what is called the clearance.

One object of my invention is to so arrange the parts that the correct distance which separates the tool-holder from the face of the grinding wheel may be readily determined by means of the drill to be ground, and this distance shall be such that the cuttin g-lips after being ground shall form, with the axial line of the drill, a common angle, whether the drill be large or small.

Another object of my invention is to provide means capable of rapid and accurate adjustment for increasing or decreasing the amount of clearance on the drill,these changes being rendered necessary because of variations in the quality or degree of hardness of the substances to be bored.

Referring to the drawings, Figure 1 is a side elevation of my improved grinding-machine. Fig. 2 is a plan view of the same, looking in the direction of the arrow. Fig. 3 is a longitudinal section 011 the line 3 3 of Fig. 2. Fig. 4 is a cross-section on the line 4 4t, and Fig. 5 is a modification.

Similar numerals of reference indicate simi lar parts in the respective figures.

A standard or base 1, which can be supported on a floor, table,or other suitable place, is provided at its top with bearings 2, in which revolves a shaft 3, having 011 oneend an emery or other grinding wheel l. Below the grinding-wheel and projecting laterally from the standard 1 is a bracket 5, from which extends a spindle 6 in parallel relation to the shaft 3. Supported bythe spindle 6 and adapted to move freely thereon is a sleeve 7, having a clampingscrew 8 for holding itin position on the spindle. Formed with the sleeve 7 and extending upwardly therefrom is a sleeve 9, which may be clamped to the spindle 10 of the tool-holding device by means of a set-screw 9 Suitable stops on the sleeve 9 and the spindle 1O limit the rotation of the tool-holding device.

The tool-holding device consists of a support 11, secured to or formed upon the upper end of the spindle 10, at an angle thereto, as shown in Fig. 1, for the purpose of properly presenting the drill-point to the grindingwheel. The upper surface of the support 11 has a longitudinal groove 12 reaching its entire length, in which fits a rib 13, formed on the under surface of the plate 1 1, sliding on the support 11 and held thereto by means of a hand-screw 16.

Pivoted at 17 to the plate let is the tool-holder proper. It consists of a guideway 18, to the up per end of which is fixed a V-grooved support 19 for the drill, one side of the support having a lip 19) forholdin g the drill in correct position for presentation to the grinding-wheel. The lower end of the guideway sustains a movable stock 20,carrying a spindle 21, adapted to slide therein and having a hand-nut for fixedly clamping the spindle. The said spindle has a head 23, slotted transversely, in which is a thumb-nut21, capable of being rotated on a screw-threaded stem 24, adapted to slide in longitudinal direction within the spindle 21 as the thumb-nut is turned. The upper end of the stem 2r carries a plate 25, beveled at the bottom to closely fit the V-grooved support 19. A screw extends downwardly from the stock through the slot in the guideway 18, where it is provided with a hand-wheel 28 for clamping the stock in place on the guide way. The screw and hand-wheel are used for roughly adjusting the stock and the plate to engage the drill. A more delicate ad j ustment of the head 23 is obtained by turning the thumb-nut 21 and advancing or retracting the stem 24: with its plate 25. A second V-grooved support is arranged to slide on the guideway 18 between the fixed support 10 and the movable stock 20, this being called into requisition when a long. drill is to be ground, so as to afford abettersupport thereto and prevent the drill from springing.

Secured to and extending laterally from the -guideway 18 is a projection 31, the upper end of which is pivoted at 17 to the plate 14, as hereinbeforementioned. An adjusting-screw 32, turning in bearings 33 on the plate 14, engages a nut 34, secured to the projection 31. By turning the screw 32 to the right or left the tool-holder will be moved on the pivot 17 a greater or less distance toward the center line of the grinding-wheel for the purpose of increasing or decreasing the amount of clearance to be given to the point of the drill. A scale 35 on the projection 31 passes under a pointer 36 as the projection is moved and indicates to the operator at a glance when the tool-holder is set to grind a drill with more or less than normal clearance.

Extending from the plate 14 and passing under the guideway 18 to its opposite side is an arm 37, its inner vertical side lying in a plane at an angle of forty degrees to a plane passing through the center line of the toolholder. From the support 11 a gage-plate 38, having a perforation 39, projects in the direction of the arm 37 and overlaps it. This perforation 39 has a diameter equal to that of the largest drill capable of being ground by the machine.

When it is desired to grind or sharpen a drill by my machine, the hand-screw 16, which secures the tool-holder to the support 11, is loosened and the tool-holder pushed u pward'until the arm 37 passes beyond the perforation 39 in the gage-plate 38. The drill is then passed down into the said perforation and the drill-holder permitted to slide down until the arm 37 strikes the drill, which in turn bears against the edge of the perforation. The hand-screw 16 is then tightened, securing the tool-holder on the support 11, with its upper end at the correct distance from the grinding-wheel for a drill of the size calipered. The drill can now be removed from the perforation 39 and placed in the V-grooved support 19, with its point projecting about one-eighth of an inch beyond the lip 19 of the support.

If the drill is a long one, the second V- grooved support 30 is moved forward to help support the drill. The stock 20 is now loosened and advanced until the plate 25 strikes the shank end of the drill, when it is tightened. The adjusting-screw 32 can now be turned to increase or decrease the amount of clearance intended to be given to the drill, this being effected by changing the horizontal angle of the tool with respect to the face of the grinding-wheel.

The machine being set as above described, the thumb-screw 21 is moved slightly to advance the drill into engagement with the grinding-wheel. As soon as this has been done the drill is held in place by the fingers of the operator and the tool-holder turned on its spindle 10 to the right, allowing the grinding of one cutting edge'of the drill and the material back of it to make the clearance. The drill is now given a half-rotation in the tool-holder and the operation repeated on the other cutting edge, and so on, reversing and grinding the bits of the drill until a satisfactory cutting edge has been produced.

In some instances the plate 14 may be dispensed with, in which case the projection 31 will slide on and be carried directly by the support 11. WVhen such a change is made, instead of usinga perforated gage-plate 38 an arm will project from the guideway 18, to which a gage-block 41 will be hinged by a vertical pivot, as represented in Fig. 5. This construction is necessary in this modified form of the invention, because otherwise the lateral movement of the tool-holder under the action of the screw 32 would move the gageblock 41 and detrimentally increase or de-v crease the distance between it and the gagearm secured to the support.

Having described my invention, I claim- 1. In a twist-drill grinder, the combination of a support having an inclined axis of oscillation, and aperforat-ed gage-plate extending laterally therefrom,a plate 14 supported by, and adapted to move longitudinally on, the support, the said plate having an arm passing under the gage-plate and adapted to coact with the perforation in the gage-plate, and a tool-holder pivoted to the plate 14, substantially as set forth.

2. In atwist-drill grinder, the combination of a support having a perforated gage-plate secured thereto, a plate, sliding on the support, provided with a gage-arm adapted to coact with the perforated gage-plate, and a pivoted tool-holder, substantially as set forth.

3. In a tool-grinding machine, the combination of an oscillating support, a tool-holder pivoted thereon, and means for laterally adjusting the tool-holder on the support, substantially as set forth.

4. In a tool-grinding machine, the combination of an oscillating support, a plate adapted to slide longitudinally thereon, and a toolholder pivoted to said plate, substantially as set forth.

5. In a twist-drill-grinding machine, the combination of an oscillating support, a plate having a longitudinal movement thereon, a tool-holder pivoted to the plate, and means for laterally adjusting the tool-holder on the plate, substantially as set forth.

6. In a tWist-drill-grinding machine, the combination of an oscillating support, a plate slidably attached thereto, a tool-holder pivoted to the plate andcapable of lateral adj ustment thereon, and a two-part calipering device, one part being secured to the plate, and the other to the support, substantially as set forth.

In testimony whereof I hereunto set my hand and affix my seal this 25th day of October, 1897.

WVILFRED EAMES. [L. s]

Witnesses:

R. O. WRIGHT, J. C. BIssELL. 

